1. Field of the Invention
The present invention relates to a method of peeling off a chip type part such as chip condenser or semiconductor chip, etc., fixed on an adhesive tape or the like and the pickup apparatus.
2. Related Background Art
In the process for manufacturing semiconductors, a semiconductor wafer is adhered to an expanded tape and diced into chips on the expanded tape, the diced chip type parts are generally peeled off from the expanded tape one by one, and the peeled chip is die-bonded in a predetermined package and is stored in a predetermined tray.
The adhesive is an adhesive tape having an adhesvie layer of an adhesive material on its surface. The adhesive material has a sufficient adhesive strength not to cause positional errors of the semiconductor devices during dicing of the semiconductor wafer into chips.
When the adhesive material which has a sufficient adhesive strength fixing a semiconductor having a back metal is used, the back metal may be peeled from the chip type part upon peeling of the chip type part from the adhesive tape. In the worst case, a deformation such as cracks in a chip type part is present.
In order to prevent the back metal from peeling off from the chip type part, the adhesive tape is irradiated with the ultraviolet beam to decrease the adhesive strength of the adhesive material before the chip type part is peeled off from the adhesive tape.
Since the entire lower surfce of the adhesive tape is irradiated with the ultraviolet beam in a conventional method, the adhesive strength of the entire adhesive tape is decreased upon radiation of the ultraviolet beam. The adhesive strength is naturally slightly decreased with a lapse of time. For this reason, assuming that the first half of chip type parts are left on the adhesive tape for current use, while the second half of chip parts are stored on the adhesive tape, the positions of the chip type parts are shifted due to an external force acting on them during storage. Therefore, storage of chip type parts on an adhesive tape is not suitable for re-storage.